package com.grand.ch05;

import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.ArrayList;

/*
*
* */
public class ObjectAnalyzer {
    private ArrayList<Object> visited = new ArrayList<>();
    /*
    * Converts an object to a string representation that lists all fields
    * @param obj an object
    * @return a string with the object`s class name and all field names and values
    * */
    public String toString(Object obj){
        if(obj == null) return "null";
        if(visited.contains(obj)) return "...";
        visited.add(obj);
        Class cl = obj.getClass();
        if(cl == String.class) return (String)obj;
        if(cl.isArray()){
            String r = cl.getComponentType() + "[]{";
            for (int i = 0; i < Array.getLength(obj) ; i++) {
                if(i > 0) r += ",";
                Object val = Array.get(obj,i);
                if(cl.getComponentType().isPrimitive()) r+= val;
                else r+= toString(val);
            }
            return r+"}";
        }
        String r = cl.getName();
        // inspect the fields of this class and all superclasses
        do{
            r += "[";
            Field[] fileds = cl.getFields();
            AccessibleObject.setAccessible(fileds,true);
            //get the names and values of all fields
            for(Field f: fileds){
                if(!Modifier.isStatic(f.getModifiers())){
                    if(!r.endsWith("[")) r+=",";
                    r+=f.getName()+"=";
                    try {
                        Class t = f.getType();
                        Object val = f.get(obj);
                        if(t.isPrimitive()) r+=val;
                        else r += toString(val);
                    } catch (IllegalAccessException e) {
                        e.printStackTrace();
                    }
                }
            }
            r += "]";
            cl = cl.getSuperclass();
        }while(cl != null);
        return r;
    }
}
